From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5C582C433DB for ; Wed, 10 Feb 2021 16:12:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 173FC64E66 for ; Wed, 10 Feb 2021 16:12:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231873AbhBJQM0 (ORCPT ); Wed, 10 Feb 2021 11:12:26 -0500 Received: from ares.krystal.co.uk ([77.72.0.130]:40310 "EHLO ares.krystal.co.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229934AbhBJQMS (ORCPT ); Wed, 10 Feb 2021 11:12:18 -0500 Received: from [51.148.178.73] (port=65008 helo=pbcllap7) by ares.krystal.co.uk with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.93) (envelope-from ) id 1l9s5R-00EyLe-Md; Wed, 10 Feb 2021 16:11:29 +0000 Reply-To: From: "John Efstathiades" To: "'Jesse Brandeburg'" Cc: , , , References: <20210204113121.29786-1-john.efstathiades@pebblebay.com> <20210204113121.29786-2-john.efstathiades@pebblebay.com> <20210204124314.00007907@intel.com> In-Reply-To: <20210204124314.00007907@intel.com> Subject: RE: [PATCH net-next 1/9] lan78xx: add NAPI interface support Date: Wed, 10 Feb 2021 16:11:09 -0000 Organization: Pebble Bay Consulting Ltd Message-ID: <005101d6ffc7$6409d8b0$2c1d8a10$@pebblebay.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Outlook 16.0 Thread-Index: AQIpfIuWVWp4oXxuaZJopfPMH/GLnQECyV9lAbFJeiOpluv9sA== Content-Language: en-gb X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - ares.krystal.co.uk X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - pebblebay.com X-Get-Message-Sender-Via: ares.krystal.co.uk: authenticated_id: john.efstathiades@pebblebay.com X-Authenticated-Sender: ares.krystal.co.uk: john.efstathiades@pebblebay.com Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Apologies for taking a while to respond. > -----Original Message----- > From: Jesse Brandeburg > Sent: 04 February 2021 20:43 > > NB: I thought I'd have a close look at this since I thought I > understand NAPI pretty well, but using NAPI to transmit frames as well > as with a usb device has got me pretty confused. I'll try to add some more rationale in the next revision of the patch. However, the short answer is that using NAPI for transmit under high load is the most effective way of getting the frames into the device's internal buffer RAM. > Also, I suspect that > you didn't try compiling this against the net-next kernel. I thought I had but it appears not. I won't let that happen again. > I'm stopping my review only partially completed, please address issues > https://patchwork.kernel.org/project/netdevbpf/patch/20210204113121.29786- > 2-john.efstathiades@pebblebay.com/ Thanks, will do, but it will take me a few weeks to sort everything out due to my other commitments. > It might make it easier for reviewers to split the "infrastructure" > refactors this patch uses into separate pieces. I know it is more work > and this is tested already by you, but this is a pretty complicated > chunk of code to review. I appreciate this is a complicated patch, a point made by another reviewer. Could you explain what you mean by "infrastructure" refactors, please? I'll certainly look at how to split this patch into smaller chunks but that might be quite hard to do. If that turns out not to possible, do you have any suggestions on how I can make the patch easier for reviewers to understand and review? John